An electrically conductive paste is used for manufacturing a printed circuit board of an electronic device. The paste contains fine particles whose main component is a metal (i.e., fine metal particles), a binder, and a liquid organic compound (solvent). By using the paste, a pattern connecting elements is printed. The paste is heated after printing. As a result of heating, fine metal particles are sintered together with other adjacent fine metal particles.
Since the pattern is obtained through printing, excellent printing characteristics are necessary for the paste. Since the paste is to be heated, excellent thermal conductivity is necessary for the paste. Since the pattern is a passage for electrons, excellent electrical conductivity is also necessary for the paste. In order to obtain these characteristics, extremely small particles (so-called nano particles) are used for the paste. The particles are flake-like. A representative material of the particles is silver.
JP2006-63414 discloses flake-like particles whose material is silver. The particles are formed through processing of spherical particles using a ball mill.